/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"

interface nsIFile;
interface nsIMIMEInfo;
interface nsIURI;

%{C++
#define NS_MIMESERVICE_CID                           \
{ /* 03af31da-3109-11d3-8cd0-0060b0fc14a3 */         \
    0x03af31da,                                      \
    0x3109,                                          \
    0x11d3,                                          \
    {0x8c, 0xd0, 0x00, 0x60, 0xb0, 0xfc, 0x14, 0xa3} \
}
%}

/**
 * The MIME service is responsible for mapping file extensions to MIME-types
 * (see RFC 2045). It also provides access to nsIMIMEInfo interfaces and
 * acts as a general convenience wrapper of nsIMIMEInfo interfaces.
 *
 * The MIME service maintains a database with a <b>one</b> MIME type <b>to many</b>
 * file extensions rule. Adding the same file extension to multiple MIME types
 * is illegal and behavior is undefined.
 *
 * @see nsIMIMEInfo
 */
[scriptable, main_process_scriptable_only, uuid(5b3675a1-02db-4f8f-a560-b34736635f47)]
interface nsIMIMEService : nsISupports {
    /**
     * Retrieves an nsIMIMEInfo using both the extension
     * and the type of a file. The type is given preference
     * during the lookup. One of aMIMEType and aFileExt
     * can be an empty string. At least one of aMIMEType and aFileExt
     * must be nonempty.
     */
    nsIMIMEInfo getFromTypeAndExtension(in ACString aMIMEType, in AUTF8String aFileExt);

    /**
     * Retrieves a ACString representation of the MIME type
     * associated with this file extension.
     *
     * @param  A file extension (excluding the dot ('.')).
     * @return The MIME type, if any.
     */
    ACString getTypeFromExtension(in AUTF8String aFileExt);

    /**
     * Retrieves a ACString representation of the MIME type
     * associated with this URI. The association is purely
     * file extension to MIME type based. No attempt to determine
     * the type via server headers or byte scanning is made.
     *
     * @param  The URI the user wants MIME info on.
     * @return The MIME type, if any.
     */
    ACString getTypeFromURI(in nsIURI aURI);

    //
    ACString getTypeFromFile(in nsIFile aFile);

    /**
     * Given a Type/Extension combination, returns the default extension
     * for this type. This may be identical to the passed-in extension.
     *
     * @param aMIMEType The Type to get information on. Must not be empty.
     * @param aFileExt  File Extension. Can be empty.
     */
    AUTF8String getPrimaryExtension(in ACString aMIMEType, in AUTF8String aFileExt);

    /*
     * Returns an nsIMIMEInfo for the provided MIME type and extension
     * obtained from an OS lookup. If no handler is found for the type and
     * extension, returns a generic nsIMIMEInfo object. The MIME type and
     * extension can be the empty string. When the type and extension don't
     * map to the same handler, the semantics/resolution are platform
     * specific. See the platform implementations for details.
     *
     * @param aType           The MIME type to get handler information for.
     * @param aFileExtension  The filename extension to use either alone
     *                        or with the MIME type to get handler information
     *                        for. UTF-8 encoded.
     * @param [out] aFound    Out param indicating whether a MIMEInfo could
     *                        be found for the provided type and/or extension.
     *                        Set to false when neither extension nor the MIME
     *                        type are mapped to a handler.
     * @return                A nsIMIMEInfo object. This function must return
     *                        a MIMEInfo object if it can allocate one. The
     *                        only justifiable reason for not returning one is
     *                        an out-of-memory error.
     */
    nsIMIMEInfo getMIMEInfoFromOS(in ACString aType,
                                  in ACString aFileExtension,
                                  out boolean aFound);
};